These studies involve derivation of transformed cell lines from the rabbit. Recent attempts have utilized the retrovirus HTLV-1 which is the causative agent in the human adult T-cell leukemia and which has been implicated in the disease tropical spastic paraparesis. Lines have been derived from the peripheral blood of rabbits infected with HTLV-1 and preliminary data show that these are T- cell lines. These cells contain DNA corresponding to HTLV-1; the precise pattern of integration and the extent of the proviral genome in the lines will be measured. Choroid plexus was taken at necropsy from a rabbit that had been infected with HTLV-1 for about 1 year and an adherent cell line has grown from this tissue. Rabbit lines that are transformed with HTLV-1 appear to be highly susceptible to infection with HIV-1. The possible reasons for this are being investigated. Collaborative studies with nephrologists at U. of Mich. are aimed at derivation of cell lines from kidneys of rabbits with experimentally induced crescentic glomerulonephritis (CGN). It has been shown in preliminary studies that the cells infiltrating the kidney in the course of this condition are T-cells and that they become activated as the disease progresses. It is our intention to characterize these cells both by their cell surface markers and by the specificity of their antigen receptors.